Explaining Recent Declines in Adolescent Pregnancy in the United States: The Contribution of Abstinence and Improved Contraceptive Use| John S. Santelli, MD, MPH, Laura Duberstein Lindberg, PhD, Lawrence B. Finer, PhD, and Susheela Singh, PhDIn recent years, the United States has had the Objectives. We explored the relative contributions of declining sexual activityhighest rate of adolescent